Fabric fringe fraying device



A ril 14, 196A PLASTOCK 3,128,526

1' w, FABRIC FRINGE FRAYING DEVICE Filed Nov. 21, 1962 4 Sheets-Sheet 1INVENTOR.

- IRVING PLASTOCK A ril 14, 1964 1. PLASTOCK FABRIC FRINGE FRAYINGDEVICE 4 Sheets-Sheet 2 Filed NOV. 21, 1962 INVENTOR IRVING PLASTOCK H Aril 14, 1964 PLASTOCK 3,128,526

FABRIC FRINGE FRAYING DEVICE Filed Nov. 21. 1962 4 Sheets-Sheet sINVENTOR. IRVING PLASTOCK A ril 14, 1964 I. PLASTOCK 3,

' FABRIC FRINGE FRAYING DEVICE Filed Nov. 21, 1962 4 Sheets-Sheet 4 DRUMDRIVE MOTOR 12 Ml cl g' l g g AMP BE E 'ETQQIVE POWER SUPPLY INVENTCR,IRVING PLASTOCK POWER I22 SUPPLY A f United States Patent C) 3,128,526FABRIC FRINGE FRAYHNG DEVICE Irving Plastoclr, 2470 64th St, Brooklyn 4,N.Y. Fiied Nov. 21, 1962, Ser. No. 239,203 17 Claims. (Cl. 2818) Thisinvention relates to fabric fraying apparatus and more particularlyconcerns apparatus for automatically fraying an edge of continuously fedwoven fabric or other sheet material to form a fringe thereat.

Different materials and different intended uses therefor, requiredifferent degrees of cutting or fraying in order to fringe the edgethereof. Most cutting mechanisms designed for fabric fraying utilizecutting means which must be fixedly secured in place prior to machineoperation. Adjustment of said cutting means requires disassembly of thecutting head, extraction of the cutting means and replacement thereof ina different position. Tools are almost invariably required to effectsuch disassembly, loosening of the cutting means securing structure,repositioning of the cutting means, retightening of the cutting meanssecuring structure, and reassembly of the cutting head. Cuttingmechanisms so constructed are inefiicient when different types ofmaterial are to be frayed one after the other and when different typesof fraying are required in successive operations of the cutting machine.

According to the present invention an apparatus assembly is providedincluding a rotatable drum in which are adjustably positionable needlesor prongs disposed to engage the warp extending lengthwise of the fabricnear .an edge thereof and to pull the warp loose from the fillingthreads or woof to form a continuous fringe along the edge of thematerial. Adjustment of the prongs is done without use of tools.Included in the apparatus is an automatically operated clamp which holdsthe material stationary while it is being frayed or fringed. Anautomatically driven conveyor carries the fabric through the apparatus.The conveyor, clamp and drum are all cyclically operated by a timingdevice so that the fabric is intermittently fed to the fraying drum andis frayed thereby. A suction duct is provided to carry away fibers orthreads pulled loose from the fabric. Once the apparatus is set up andoperating it will feed and fray fabric continuously. The apparatus canbe used for fraying .woven or non-woven fabric, paper, plastic film,metal foil, etc.

It is therefore a principal object of the invention to provide anapparatus for automatically fraying or fringing an edge or margin ofsheet material.

It is a further object to provide a fabric fraying apparatus with novelquickly adjustable cutting or tearing means.

Another object is to provide a cutting mechanism in a fraying deviceincluding a rotatable drum having fabric engaging prongs extendingradially therefrom and adjustable cam means in the drum for adjustingthe extent of radial projection of the prongs from the drum.

Other objects are to provide a fraying apparatus with cyclic controlmeans for feeding, clamping and fraying sheet material; to provideadjustable fabric fraying prongs which can be set without use of tools;to provide novel clamping means for fabric being frayed; and to providenovel conveyor means for fabric in a fraying apparatus.

For further comprehension of the invention, and of the objects andadvantages thereof, reference will be had to the following descriptionand accompanying drawings, and to the appended claims in which thevarious novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

FIG. 1 is a perspective view of fraying apparatus embodying theinvention.

FIG. 2 is a vertical sectional view on an enlarged scale of part of theapparatus of FIG. 1, certain portions being shown in side elevation.

FIG. 3 is a fragmentary sectional view of part of the fraying mechanismtaken on line 33 of FIG. 2, showing the prongs in one position.

FIGS. 4 and 5 are sectional views similar to FIG. 3 showing the prongsin two different positions of adjustment.

FIG. 6 is a side elevational view on an enlarged scale of a frayingmember including prong and spring.

FIG. 7 is an end elevational view of the apparatus of FIG. 1, some partsbeing omitted.

FIG. 8 is a vertical sectional view of part of the apparatus, taken online 88 of FIG. 1.

FIG. 9 is a side elevational view of a fabric clamp employed in theapparatus.

FIG. 10 is a diagram of the control system employed in the apparatus.

Referring to the drawings, there is shown in FIG. 1 the apparatus 10including a cylindrical drum 12 which constitutes a fabric cutting orfraying head of the apparatus. The drum is rotatably mounted on an axialshaft 11 journaled in bearing brackets 14, 16 at opposite ends. Thebrackets are secured to a horizontal table 18. At one end of shaft 11 isa pulley 20 driven by a belt 22 entrained on pulley 24 of a motor 26.The motor is mounted on a stand 28 secured to the table 18. A pluralityof axially adjustable prongs 30 extend radially from the drum throughchannel openings 32 therein. The prongs are arranged in a plurality ofcircumferential columns and axial rows. As best shown in FIG. 7, prongs3d are omitted from a circumferential portion P of the drum, for apurpose subsequently explained. A prong adjustment knob 34 and prongsetting knob 36 are conveniently located at one end of the drum. Knob 34has an index finger or pointer 35 which is movable around a scale 37marked on end wall 38 of the drum.

Disposed underneath the drum 12 is a clamp 40. This clamp, as best shownin FIGS. 1, 2, 7 and 9, is a plate folded to a generally U-shaped crosssection. The rounded bight 42 of the plate defines a springy, elasticjoint which normally holds upper plate section 44 spaced from lowerplate section 46. Plate section 46 is secured by screws 48 insertedthrough holes 50 into the table 18. Both plate sections have spacedrounded knob-like projections 52, 54 extending inwardly of the clamp.Projections 52 extend upwardly from the inner, upper side of platesection 46 while projections 54 extend downwardly from the inner, lowerside of plate section 44. -A rectangular cutout or hole 45 is formed inthe clamp extending from the bight 42 outwardly toward the free edges ofthe plate sections but terminating short thereof. This hole is locatedso that prongs 30 can engage an edge or margin M of fabric F which isfed longitudinally through the clamp.

The upper movable plate section 44 has an extension 49 at its outeredge. This plate extension carries ears .53 which engages a link 55pivotally secured to the upper end 51 of a plunger 56 which movesaxially in a solenoid 58. Plunger 53 passes through hole 59 in thetable. The solenoid is secured to the underside of the table as shown inFIGS. 1 and 7. A coil spring 60 inside the solenoid restores the plungerto its axially upward extended position when the solenoid isdeenergized. When the solenoid is energized, the fabric F is engagedbetween the plate sections 44, 46 as the plunger pulls down platesection 44.

A suction duct 62 is located near the drum 12. The open end 61 of theduct is parallel to the axis of the drum. The duct terminates at asuction source (not shown).

The table 13 has a rectangular cutout or hole '76 through which extendsthe upper sides of two axially parallel rollers '72 and '73. The uppercourse '74 of an endless belt 71 is located just above the tablecoplanar with the upper or inner side of plate section 46. An idlerpressure roller '75 carried by bearing brackets 76 on the table extendsacross the belt and applies pressure on the upper surface of fabric F toadvance the fabric lengthwise away from the drum and clamp. The belt 71serves as a conveyor and is driven by a motor Sit; see FIG. 8. The motor30 is mounted on a shelf 82 under the table. The motor has a drivepulley 84 which drives a belt 86 entrained on pulley 88. Pulley 88 issecured to the shaft 90 of roller 73. Rollers '72, 73 are rotatablysupported by bearing brackets 91, 92 underneath the table.

The motor 80, solenoid 58 and motor 26 are connected in a common controlcircuit housed in a control box 87 underneath the table. This controlbox has a control switch 95 manually operable at the front edge of thetable; see FIG. 1.

The drum 12 has an inner cylindrical cavity 105 in which is a rotatablecylindrical cam 102; see FIGS. 2-5. This cam is fluted or groovedlongitudinally. The ridges 104 and grooves 106 extend from end to end ofthe cam. The cam is loosely mounted on shaft 11 and can be rotatedmanually with respect to the shaft and drum by turning knob 34. Shaft 11is secured to end walls 38, 38 of the drum which are in turn secured tothe outer cylindrical wall 12 of the drum. Channels 32 extend radiallythrough the wall 12*. These channels have enlargements 32 at their innerends open to the cam Hi2.

Prongs 30, as clearly shown in FIGS. 26, have pointed outer ends 31 andcylindrical inner ends 31. Circumferential flanges 108 are secured tothe prong ends 31', and coil springs 110 are axially mounted on theprongs. These springs bear on the flanges 198 and on annular seats 112formed at the radially outer ends of channel enlargements 32 The prongshave rounded free ends 31" which contact the ridges and grooves of thecam due to the radially inward bias exerted by the springs 110. Acircumferentially arranged series of holes or recesses 113 is formed onone end of cam 102; see FIGS. 2 and 5.

A stud 114 secured to knob 36 is frictionally fitted in hole 116 in endplate 38. This stud is axially movable and can be inserted into any oneof holes 113 to retain the cam in any position of rotational adjustmenton shaft 12. By rotation of the cam, the several rows of prongs 3% canbe selectively extended or retracted as the rounded ends 31 engagedifferent portions of the ridges 1M. and grooves 106 as illustrated inFIGS. 3-5.

FIG. illustrates schematically the automatic control system of theapparatus. Drum 12 with prongs 3i) projecting therefrom is operativelyconnected to and driven by motor 26. A continuously energized timingmotor 120 is connected to power supply terminals 122 and is controlledby the On-Off switch 95. The timing motor rotates a shaft 124 of atiming disk 12%. This disk is an insulated member on which are twoarcuate, circumferentially spaced, fixed electrically conductivecontacts 128, 130. Contact arm 132 is secured to shaft 124 and ridesover contacts 128, 13% in turn and in continuous succession. Powersupply terminal 134 is connected to a wiper 136 which continuouslycontacts shaft 124. Contact 128 is connected to one terminal of the beltdrive motor 80. The other terminal of motor 80 is connected to powersupply terminal 135. Contact 13% is connected to common, connectedterminals 140, 142 of motor 26 and solenoid 58. The other terminals 141,143 of the motor 26 and solenoid are connected together to power supplyterminal 135.

In operation of the apparatus, upon closing of switch 95, the timingmotor is continuously energized and continuously drives shaft 124. Thedrum drive motor 26 and the clamp actuating solenoid 53 aresimultaneously energized when arm 132 rides over contact 13 1 When arm132 rides over contact 128, the motor 26 and solenoid 58 are deenergizedand motor is energized. When the drum is driven, the prongs 36 arecarried through the opening 45 in clamp 46 and engage the warp threadsat the edge M of the fabric F. The clamp plate sections are closed bythe solenoid and grip the opposite edge of the fabric therebetween. Thefabric is stationary because motor 80 is stopped. The prongs tear thewarp threads loose from the remainder of the fabric and pull them out ofthe clamp. To assist in tearing the warp loose, a series of slits S canbe made in the edge M of the fabric as shown in FIG. 1. The opposingedges of the bight 42 at hole 45 of the clamp 40 can be sharpened at 42'as shown in FIG. 9. As the warp threads are pulled outwardly by theprongs they will be cut at opposite sharp edges i2. This will leaveshort lengths of warp threads engaged by the prongs. As the drum 12rotates, the suction applied through duct 62 will effectively remove theengaged warp threads. Slots or grooves 63 can be formed in the upperside of the table to receive and permit passage of the pointed ends ofthe prongs as shown in FIG. 2, while the drum rotates.

After the drum makes one or more revolutions, and when the portion P ofthe drum which is free of prongs is opposite the clamp, the drum isstopped and simultaneously the solenoid is deenergized to open theclamp. The motor 80 is then energized and advances the newly frayed orfringed portion of the fabric out of the clamp over the belt 71. Afterthe fabric is advanced a predetermined distance, which may be more orless than the longitudinal length of hole 45 in the clamp, the motor 80is stopped and the clamp is actuated to grip the fabric While the drumrotates to fray the portion of the fabric edge M exposed at hole 4'5.

The edge M of the fabric can be frayed or fringed continuously or atpredetermined spaced intervals depending on the timing of the controlsystem. To change the spaced intervals of fraying, the timing disk 126may be replaced by another disk in which the arcuate contacts 128, havedifferent arouate lengths.

To change the radial extensions of the prongs 30 for fraying differentthicknesses of fabric or for fraying plural layers of fabricsimultaneously, the knob 34 is turned to advance or retract the prongsradially of the drum. Re setting of knob 36 fixes the new positions ofthe prongs.

The apparatus described thus makes it possible to fray an edge of afabric sheet continuously and automatically for forming fringes or slitstherein. If the sheet is woven cloth, a fringed edge will be produced inwhich the woof or filling threads are free from the warp. If the sheetis plastic film, paper, metal foil or other non-woven or nonfibrousmaterial, a series of slits extending transversely of one edge of thesheet will be formed in the apparatus. Such frayed, fringed or slitmaterials are useful in fabrieating garments, trimmings for windowdisplays, Christmas tree decorations, etc.

While I have illustrated and described the preferred embodiment of myinvention, it is to be understood that I do not limit myself to theprecise construction herein disclosed and that various changes andmodifications may be made within the scope of the invention as definedin the appended claims.

Having thus described my invention, what I claim as new, and desire tosecure by United States Letters Patent is:

1. A fraying device: comprising (a) support means;

(b) drum means carried by said support means for rotation about apredetermined axis of rotation;

(c) a plurality of cutting means;

(d) mounting means interconnecting said cutting means for both conjointrotational movement with said drum means and for movement with respectto said drum means along radial lines intersecting said axis ofrotation;

(e) cam means coacting with said plurality of cutting means to positionsame at different radial distances from said axis of rotation;

(f) selection means for operating said cam means to so position saidcutting means;

(g) said dnurn means comprising a hollow cylinder having formed thereina plurality of channels arranged in parallel rows and columns, saidplurality of channels including shoulder portions formed therein;

(h) each of said plurality of cutting means being d1sposed in one ofsaid channels; and

(i) a spring disposed ineaoh of said channels against said shoulderformed therein, said spring biasing said cutting means towards said axisof rotation;

(j) said cam means determining the extent of movement of said cuttingmeans towards said axis of rotation.

2. A fraying device: comprising (a) support means;

(b) drum means carried by said support means for rotation about apredetermined axis of rotation;

(c) a plurality of cutting means;

(d) mounting means interconnecting said cutting means for both conjointrotational movement with said drum means and for movement with respectto said drum means along radial lines intersecting said axis ofrotation;

(e) cam means coacting with said plurality of cutting means to positionsame at different radial distances from said axis of rotation; and

(f) selection means for ope-rating said cam means to so position saidcutting means;

(g) said cam means having a configuration adapted to position certainones of said plurality of cutting means at a first distance from saidaxis of rotation while positioning other ones of said plurality ofcutting means at a second distance from said axis of rotation;

(h) said configuration of said carn means providing a position on saidcam means wherein said first distance is such that said certain ones ofsaid cutting means do not extend beyond the surface of said drum means,said other ones of said cutting means at said position extending fromsaid drum so that said second distance is a maximum.

3. A fraying device: comprising (a) support means;

([7) drum means carried by said support means for rotation about apredetermined axis of rotation;

(c) a plurality of cutting means;

(d) mounting means interconnecting said cutting means for both conjointrotational movement with said drum means and for movement with respectto said drum means along radial lines intersecting said axis ofrotation; I

(e) cam means coacting with said plurality of cutting means to positionsame at different radial distances from said axis of rotation; and

(1) selection means for operating said cam means to so position saidcutting means;

(g) said cam means having a configuration adapted to position certainones of said plurality of cutting means at a first distance from saidaxis of rotation while positioning other ones of said plurality ofcutting means at a second distance from said axis of rotation;

(11) said configuration of said cam means providing a position on saidcam means wherein said first dis tance is such that said certain ones ofsaid cutting means do not extend beyond the surface of said drum means,said other ones of said cutting means at said position extending fromsaid drum so that said second distance is a maximum;

(i) said configuration of said cam means providing another position onsaid cam means wherein said first distance and said second distance areequal.

4. A fraying device: comprising (a) support means;

(b) drum means carried by said support means for rotation about apredetermined axis of rotation;

(c) a plurality of cutting means;

(d) mounting means interconnecting said cutting means for both conjointrotational movement with said drum means and for movement with respectto said drum means along radial lines intersecting said axis ofrotation;

(e) cam means coacting with said plurality of cutting means to positionsame at dilferent radial distances from said axis of rotation; and

(f) selection means for operating said cam means to so position saidcutting means;

(g) said cam means having a configuration adapted to position certainones of said plurality of cutting means at a first distance from saidaxis of rotation while positioning other ones of said plurality ofcutting means at a second distance from said axis of rotation;

(h) said cam means having a generally cylindrical configurationconcentric with said drum means, the peripheral surface of said cammeans engaging said cutting means to position same;

(i) said peripheral surface having a circumferentially ridged andgrooved configuration.

5. In a cutting mechanism for fraying material having a table and arotatable cylindrical drum mounted on supports extending above saidtable with the axis of rotation of said drum parallel to the top of saidtable, the

invention comprising (a) a hollow formed in the center of said drum;

(b) a plurality of radial substantially circular guide channels formedin said drum extending from the outer to the inner surface thereof, saidguide channels being disposed in a plurality of rows parallel to theaxis of rotation and in a plurality of columns perpendicular to the axisof rotation;

(c) said guide channels further having formed therein a shoulder;

(d) a plurality of substantially circular needle-like fraying memberseach disposed in one of said guide channels;

(e) an annular ledge formed on each of said fraying members;

(i) a spring disposed in each channel between said shoulder formedtherein, and said ledge formed on said cutting members, said springsurrounding said fraying member and biasing same radially inwardlytowards said axis of rotation;

(g) a cam disposed in said hollow formed in said center of said drum,said cam having a configuration such that it engages all 'saidicuttingmembers to determine the extent of movement thereof towards said axis ofrotation, said configuration positioning said cutting members which aredisposed in any one of said rows at the same radial distance from saidaxis of rotation, said configuration further positioning said cuttingmembers which are disposed in any of said columns such that theyconstitute two different groups, said first group of cutting membersextending a different radial distance than said second group of cuttingmembers; and

(h) selection means interconnected with said cam means to selectivelyposition same and thereby vary F7 said first and said second radialdistance at which said cutting members extend from said axis ofrotation.

6. In a cutting mechanism for fraying material having a table and arotatable cylindrical drum mounted on supports extending above saidtable with the axis of rotation of said drurn parallel to the top ofsaid table, the invention comprising (a) a hollow formed in the centerof said drum;

(b) a plurality of radial substantially circular guide channels formedin said drum extending from the outer to the inner surface thereof, saidguide channels being disposed in a plurality of rows parallel to theaxis of rotation and in a plurality of columns perpendicular to the axisof rotation;

(c) said guide channels further having formed therein a shoulder;

(d) a plurality of substantially circular needle-like fraying memberseach disposed in one of said guide channels;

(e) an annular ledge formed on each of said fraying members;

( a spring disposed in each channel between said shoulder formedtherein, and said ledge formed on said cutting members, said springsurrounding said fraying member and biasing same radially inwardlytowards said axis of rotation;

(g) a cam disposed in said hollow formed in said center of said drum,said cam having a configuration such that it engages all said cuttingmembers to determine the extent of movement thereof towards said axis ofrotation, said configuration positioning said cutting members which aredisposed in any one of said rows at the same radial distance from saidaxis of rotation, said configuration further positioning said cuttingmembers which are disposed in any of said columns such that theyconstitute two difierent groups, said first group of cutting membersextending a different radial distance than said second group of cuttingmembers; and

(h) selection means interconnected with said cam means to selectivelyposition same and thereby vary said first and said second radialdistance at which said cutting members extend from said axis ofrotation;

(i) said configuration also including a position at which said firstgroup of cutting members are retracted to the same radial distance fromsaid axis of rotation as the outer surface of said drum, and at whichsaid second group of cutting members are extended to a predeterminedmaximum radial distance from said axis of rotation;

(j) said configuration further including a position at which said firstgroup of cutting members and said second group of cutting members extendidentical radial distances from said axis of rotation.

7. In a cutting mechanism for fraying material having a table and arotatable cylindrical drum mounted on supports extending above saidtable with the axis of rotation of said drum parallel to the top of saidtable, the invention comprising (a) a hollow formed in the center ofsaid drum;

(b) a plurality of radial substantially circular guide channels formedin said drum extending from the outer to the inner surface thereof, saidguide channels being disposed in a plurality of rows parallel to theaxis of rotation and in a plurality of columns perpendicular to the axisof rotation;

(c) said guide channels further having formed therein a shoulder;

(d) a plurality of substantially circular needle-like fraying memberseach disposed in one of said guide channels;

(e) an annular ledge formed on each of said fraying members;

(f) a spring disposed in each channel between said shoulder formedtherein, and said ledge formed on said cutting members, said springsurrounding said fraying member and biasing same radially inwardlytowards said axis of rotation;

(g) a cam disposed in said hollow formed in said center of said drum,said cam having a configuration such that it engages all said cuttingmembers to deter-mine the extent of movement thereof towards said axisof rotation, said configuration positioning said cutting members whichare disposed in any one of said rows at the same radial distance fromsaid axis of rotation, said configuration further positioning saidcutting members which are disposed in any of said columns such that theyconstitute two different groups, said first group of cutting membersextending a different radial distance than said second group of cuttingmembers;

(h) selection means interconnected with said cam means to selectivelyposition same and thereby vary said first and said second radialdistance at which said cutting members extend from said axis ofrotation; and

(1') locking means settable at each position of said cam to lock saidcam and drum for conjoint rotation.

8. A fringe fraying mechanism of the class described:

comprising (a) a table;

(b) spaced supports extending from said table;

(c) aligned bearings carried by each of said spaced supports;

(d) spaced stub shafts each journalled in one of said aligned bearings;

(e) spaced end plates each secured to one of said stub shafts;

(f) a hollow cylindrical drum secured to and occupying the space betweensaid spaced end plates;

(8) a plurality of guide channels formed in said cylindrical drum, saidplurality of guide channels being arranged in a plurality of rows andcolumns;

(h) a shoulder formed in each guide channel;

(1) a cutting member having a ledge affixed thereto disposed in each ofsaid guide channels;

(j) a spring disposed in each of said guide channels between saidshoulder formed therein and said ledge afiixed to said cutting member,surrounding said cutting member to urge same towards the axis ofrotation of said cylindrical drum;

(k) a cam means positioned in the hollow of said cylindrical drumcoacting with said cutting members to determine the extent of movementthereof towards the axis of rotation of said cylindrical drum;

(1) a shaft secured to said spaced end plates mounting said cam forrotation therebetween;

(m) a plurality of recesses formed in said cam on the side thereofadjacent one of said end plates;

(n) a stud, passing through an aperture in said one end plate, adaptedto be seated in any one of said plurality of recesses to interconnectsaid cam and end plate for conjoint movement;

(0) a knob positioned on the side of said one end plate opposite saidcam and secured to said stud to facilitate movement thereof into and outof each of said plurality of recesses;

(p) a selection knob interconnected to said cam to effect rotationthereof to selected settings each of said settings corresponding to aposition of alignment between each of said plurality of recesses andsaid stud; and

(q) drive means for conjointly rotating said stub shafts,

end plates, cylindrical drum and cam;

(r) said cutting members when rotated by said rotating drum passingthrough any material placed between said rotating drum and said table tofray the material and form a fringe thereon.

9. A fabric fraying apparatus comprising:

'(a) a support;

'(b) a drum rotatably mounted above said support;

() fabric engaging prongs extending radially from said drum andadjustably extensible from the drum;

(d) fabric clamping means disposed on said support underneath the drum;

'(e) means for drawing said fabric through said clamping means;

(1) motor means for rotating the drum;

(g) means for actuating said clamping means; and

(h) control means alternately actuating the fabric drawing means and thedrum rotating means.

10. A fabric fraying apparatus comprising:

(a) a support;

(b) a drum rotatably mounted above said support;

(0) fabric engaging prongs extending radially from said drum andadjustably extensible from the drum;

(d) fabric clamping means disposed on said support underneath the drum;

(e) means for drawing said fabric through said clamping means;

(7) motor means for rotating the drum;

(g) means for actuating said clamping means; and

(h) control means alternately actuating the fabric drawing means aloneand simultaneously actuating the fabric clam-ping means and drumrotating means.

11. A fabric fraying apparatus comprising:

(a) a support;

(b) a drum rotatably mounted above said support;

(0) fabric engaging prongs extending radially from said drum andadjustably extensible from the drum;

(d) fabric clamping means disposed on said support underneath the drum;

(e) means for drawing said fabric through said clamping means;

( motor means for rotating the drum;

(g) means for actuating said clamping means;

(h) control means alternately actuating the fabric drawing means aloneand simultaneously actuating the fabric clamping means and drum rotatingmeans;

1(1') said clamping means comprising a plate having a generally U-shapedcross section with a springy bight;

(j) a rectangular opening in said plate at said bight for extension ofsaid prongs therethrough to engage an edge of fabric disposed inside theplate; and

(k) projections on inner sides of facing sections of the plate forgripping the fabric when said sections are closed together.

12. A fabric fraying apparatus comprising:

(a) a support;

(b) a drum rotatably mounted above said support;

(0) fabric engaging prongs extending radially from said drum andadjustabiy extensible from the drum;

(d) fabric clamping means disposed on said support underneath the drum;

(e) means for drawing said fabric through said clamping means;

(1) motor means for rotating the drum;

(g) means for actuating said clamping means;

(it) control means alternately actuating the fabric drawing means aloneand simultaneously actuating the fabric clamping means and drum rotatingmeans;

(i) said clamping means comprising a plate having a 10 generallyU-shaped cross section with a springy bight;

(j) a rectangular opening in said plate at said bight for extension ofsaid prongs therethrough to engage an edge of fabric disposed inside theplate; and

(k) projections on inner sides of facing sections of the plate forgripping the fabric when said sections are closed together;

(I) said means for actuating said clamping means comprising a solenoidhaving a plunger operatively connected to one section of said plate formoving the same against the other section.

13. A fabric fraying apparatus according to claim 12, wherein said meansfor drawing the fabric through said clamping means includes:

(a) an endless belt;

(b) a motor driving said belt; and

(c) a cooperating idler roller contacting one course of the belt whilesaid fabric isconveyed on the belt.

14. A fabric fraying apparatus according to claim 13,

wherein said control means includes:

(a) a continuously driven timing switch device; and

(b) circuit means interconnecting said timing switch device with thedrum driving motor means, belt driving motor and solenoid.

15. A fabric fraying apparatus according to claim 11, wherein the bightof said plate has sharpened edges at opposite ends of said rectangularopening for cutting warp threads of the fabric engaged by said prongsduring rotation of the drum.

16. A fabric fraying apparatus according to claim 15, further comprisinga suction duct disposed adjacent to the drum for carrying away pieces ofthread torn from the fabric and engaged upon said prongs.

17. A fabric fraying apparatus comprising:

(a) a support;

([2) a drum rotatably mounted above said support;

(0) fabric engaging prongs extending radially from said drum andadjustably extensible from the drum;

(d) fabric clamping means disposed on said support underneath the drum;

(e) means for drawing said fabric through said clamping means;

(f) motor means for rotating the drum;

(g) means for actuating said clamping means;

(h) means for drawing off from said prongs portions of the fabricengaged on the prongs during rotation of the drum; and

(i) control means for alternately actuating the fabric drawing meanswhile the drum is stationary and clamping means is inactive, and forsimultaneously actuating the clamping means to clamp the fabric androtating the drum to engage the prongs in said fabric, While the fabricdrawing means remains stationary.

References Cited in the file of this patent UNITED STATES PATENTS661,605 Hafter Nov. 13, 1900 715,378 Heath Dec. 9, 1902 814,947 Dube eta1. Mar. 13, 1906 861,661 King July 30, 1907 2,475,170 ZieVe July 5,1949

9. A FABRIC FRAYING APPARATUS COMPRISING: (A) A SUPPORT; (B) A DRUMROTATABLY MOUNTED ABOVE SAID SUPPORT; (C) FABRIC ENGAGING PRONGSEXTENDING RADIALLY FROM SAID DRUM AND ADJUSTABLY EXTENSIBLE FROM THEDRUM; (D) FABRIC CLAMPING MEANS DISPOSED ON SAID SUPPORT UNDERNEATH THEDRUM; (E) MEANS FOR DRAWING SAID FABRIC THROUGH SAID CLAMPING MEANS; (F)MOTOR MEANS FOR ROTATING THE DRUM; (G) MEANS FOR ACTUATING SAID CLAMPINGMEANS; AND (H) CONTROL MEANS ALTERNATELY ACTUATING THE FABRIC DRAWINGMEANS AND THE DRUM ROTATING MEANS.